Improvement in saw-mill dogs



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SAW MILL DOGS.

Patented April 11 1816.

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N.PETER$, PHDTO-LITHOGRAPM ER, WASHINGTON. D C,

I UNITED vSTMas PATENrOrrroE.

ALBERT CUNNINGHAMQOF MILWAUKEE, WISCONSIN, ASSIGNOR TO OHN M. sTovvELL,or SAME'PLAOE.

IMPROVEMENT IN SAW- MILL Specification forming partof Letters Patent No.175,855, dated April 11,1876; application filed September 5, 1874.

To all whom it may concern Be it known that I, ALBERT CUNNINGHAM, of thecity of Milwaukee, in the county of Milwaukee and State of Wisconsin,have invented certain new and useful Improvements in Saw-Mill Dogs; andI do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it pertains to make and use it, reference being had to theaccompanying drawings, which form a part of this specification.

My invention consistsof an improved device for firmly attaching a stickof timber to the head-block or carriage of a saw-mill While it is beingsawed.

Figure l is aview of the whole device as it appears when detached fromthe standards. Y and Z are two separate sets of 'dogs, suitably attachedto the ordinary standards used on the head-block or carriage of asaw-mill, and which are similar in construction. They are connectedtogether by the shaftR R in such a manner that both move together. Theshaft R R is formed of two separate pieces, connected by the featheredsleeve S, permitting it to be slightly shortened and extended, and alsoprovided with ,a universal joint, Q Q, near each extremity. Instead ofsleeve S, a slot in the end of the shaft, at one or both the universaljoints, may be used but I prefer the feathered sleeve. The shaft B Rworks in bearings in the bed-plates A A of the standards Y Z. I

Fig. 2 is a representation of one of the sets of dogs, in which A A isthe bed-" plate. I I I are double-toothed dogs, pivoted to the bed-plateA at c a c, and connected by the bar D, which is, at M, connected withthe lever B, at N, by means-of the conmeeting-rod O. The lever B iskeyed upon the shaft R R. H is a plate, to which are attached thestraight teeth b b b. It is formed with the oblique slots K K, throughwhich bolts extend into the bed-plate A A, and which serve to guide theplate H in its motion. E is an arm, pivoted to the bed-plate at p, andhaving the two projections l and is, between which the cam F, attachedto the shaft R R, works. At G the arm E is attached to the plate H bymeans of a pin working in a slot. P is a weighted pawl, pivoted to leverB at m, and working into the ratchet 9. On the side of the leveropposite the pawl is fastened the spring f, which crowds the flat-headedpin i through the lever, so that its point slightly projects. r

Fig. 3 shows the form of the dog I. It is formed with two curved teethor hooks, Whose outline corresponds, allowing a slight clearance withthe arc of a circle struck.

from c as a center, and the dog should be so placed on the bed-plate asto make point a strike a flatsurface placed close to the standard at anapproximate angle of thirty degrees. The point 01 is madeasuitabledistance, usually about an inch and a half farther from the center thanthe point a. In operation the point a protrudes only about one-half ofaninch from the standard, and is useful chiefly for dogging a flatsurface, as a log already slabbed. When rough uneven surfaces aredogged, the secondary hook or tooth d is brought into use.

The operation of my improved dog is as follows: When the log is placedinproper position and the standards are adjusted to it, an

upward movement of the lever B forces the points a a a of the dogs I I Idownward and into the log; or, if the surface of the log be rough oruneven, the points a a a, slipping by the points d d d, are brought downand forced into the log. At the same time the plate H is forced upwardand outward in an oblique line, and drives the straight dogs I) b 11into the log. In this position all parts may be locked by the pawl 1?.When the pawl P is raised to release the lever its edge strikes thepoint of pin 2', forces it in, and is held by it until the parts are allreturned to their former position, when it is hit by the projection ofthe bed-plate and released.

On account of the jointed connecting-shaft R R, the sets of the dogs Yand Z may be advanced or drawn back independently without affectingtheir simultaneous projection by means of lever B. Instead of attachingthe bed-plates A A to the standards, they may be attached to thehead-blocks and serve as standards. The relative position of thestraight and curved dogsmay also be'ch'anged.

I am aware that a curved dog working on a pivot has been heretoforeused, and I donot claim such a one, broadly. I am also aware that ashaft has been used to connect two sets 7 of saw-mill dogs, and I do notclaim such a shaft, broadly but Iclaim as my invention-'- 1. Incombination with two sets of dogs attached to a saw-mill carriage, theshaft R R, provided with the universal joints Q Q, andwiththe extensionfeathered couplingsleeve S.

2. The dog I, having two teeth or hooks, substantially as and for thepurposes set forth.

3. The combination of lever B, pawl 1?, spring f, and pin t,substantially as and for "thepurposes "set forth. v

4. The combination of lever B, cam F, arm E, and plate H, substantiallyas and for the purposes set forth. I

5. The combinatiou'of leverB, pawl P, and ratchet g, substantially asand for the purposes described. N

In testimony that I claim the foregoing I have hereunto set my hand this26th day of August, 1874. v

. ALBERT CUNNINGHAM. 1 I Witnesses:

' E. H. BOTTUMV G. P. MARTIN.

